Acute effects of short term use of e-cigarettes on airways physiology and respiratory symptoms in smokers with and without airways obstructive diseases and in healthy non smokers

Abstract

BACKGROUND Although the use of e-cigarettes is increasing worldwide, their short and long-term effects remain undefined. We aimed to study the acute effect of short-term use of e-cigarettes containing nicotine on lung function and respiratory symptoms in smokers with airways obstructive disease (COPD, asthma), "healthy" smokers, and healthy never smokers. METHODS Respiratory symptoms, vital signs, exhaled NO, airway temperature, airway resistance (Raw), specific airway conductance (sGaw) and single nitrogen breath test were assessed before and immediately after short term use of an e-cigarette containing 11mg of nicotine among adults with COPD, asthma, ''healthy" smokers, and never-smokers. The effect of the use of nicotine-free e-cigarettes among ''healthy" never smokers was also studied. RESULTS The majority of participants reported acute cough. Short term use of nicotine e-cigarettes was associated: a) with increased heart rate in all subjects except in the COPD group, b) decreased oxygen saturation in "healthy" and COPD smokers, c) increased Raw in asthmatic smokers, "healthy" smokers, and healthy never smokers, d) decreased sGaw in healthy subjects, and e) changed slope of phase III curve in asthmatic smokers. Short-term use of nicotine-free e-cigarettes increased Raw and decreased sGaw among healthy never smokers. CONCLUSIONS Short-term use of an e-cigarette has acute effects on airways physiology and respiratory symptoms in COPD smokers, asthmatic smokers, "healthy" smokers and healthy never smokers. E-cigarette use was associated with effects in ''healthy" never smokers irrespectively of nicotine concentration. More studies are needed to investigate both short and long-term effects of e-cigarette use

Short‐term respiratory effects of e‐cigarettes in healthy individuals and smokers with asthma

“…The MA, however, expressed this pattern more prominently, as they exhibited a significantly higher degree of changes for Z5, R5 and R10 than the HS and a significant decrease in X5 that was insignificant in the HS. These results complement previous findings that showed increased airway resistance (Raw) in HS and asthmatic smokers …”

“…E‐cigarette smoking (ECS) has been shown to be associated with respiratory symptoms, immediate pulmonary dysfunction and oxidative stress expressed as increased flow resistance and reduced fractional exhaled nitrogen oxide (FeNO) . However, the time course of such alterations has not been previously examined and the duration of the immediate pulmonary effects of ECS is not known.…”

“…Furthermore, it is known that combustible cigarette smoking (CCS) has more inflammatory effects in smokers with asthma compared to healthy smokers (HS) . Limited studies on the effects of ECS on asthma have shown increased asthma symptoms and severity . However, there has been no systematic comparison of the pulmonary effects of ECS between healthy people and those with asthma.…”

Electronic cigarettes: a task force report from the European Respiratory Society

“…A human study (30 smokers versus controls) showed that acute inhalation of ECIG vapour increased respiratory impedance and airway resistance, but did not immediately impact forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio [100]. Another study showed an acute effect of ECIGs on airway resistance, showing increasing of airway resistance in asthmatic smokers, healthy smokers and never-smokers (ECIGs with and without nicotine) [101]. A separate study with 15 smokers and 15 controls found no effect of acute ECIG exposure on lung function as determined by FEV1/FVC ratio [102].…”

“…Health effect studies are difficult to design because most ECIG users are either past or current cigarette smokers. Short-term, experimental use of ECIGs has been shown to have acute effects on airways physiology and respiratory symptoms in COPD smokers, asthmatic smokers, "healthy" smokers and healthy never-smokers [101]. Common adverse effects include throat irritation and cough [182].…”